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fulhamphil
14th July 2008, 01:15 PM
Hi Everybody, I tried out my new 50-200swd on my E-3 yesterday, and while i'm a complete novice at wildlife photography, i must admit i was a little dissapointed with my results, i know i will have to practice plenty before my results improve. Having never used C-AF before, i had a go trying to track birds in flight, but tbh i wasn't really sure on how to get the best from C-AF, any tips or advice on how to use it succesfully would be very much appreciated, thanks, Phil:confused:

Invicta
14th July 2008, 06:23 PM
C-AF is one of the most difficult topics to get working effectively. Even with the best results expect a high percentage of reject photos.

For birds in fight you will need a fast shutter speed to freeze the action.

Have a look at Wrotniak's article for C-AF related setting such as Release Priority C and Continuous AF Lock.

http://www.wrotniak.net/photo/43/e3-sett.html

250swb
31st July 2008, 07:42 AM
Practice makes perfect and only analyzing failed pictures will teach you. But C-AF is pretty much about pointing the lens in the right direction and pressing the shutter. However other things make a big difference to how it works.

The first thing is to make sure image stabilisation is in IS-2 mode for tracking shots. I have also found that dynamic single focus point does not work very well, so just use a set focus point. And obviously make sure your ISO and shutter speed are fast enough to stop the birds motion.

Steve

PeterD
31st July 2008, 08:04 AM
I have experimented with C-AF for bird shots but have to say I have had no success with it. The problem for me was that, as the bird flew around tree tops I would get most shots mis-focussed. I guess this method would be ideal for fast moving action in say motor sport where the frame is held and the only object moving is the subject. I now only ever use S-AF.

I would be very interested in anyone else's experience/comments as I hate to give up on anything.

Peter

Mark Roberts
1st September 2008, 07:14 AM
I'm no expert on anything, but I did put a similar question to the dpreview forum and was told that action shooters switch the Fn and AEL buttons (end of spanner B menu) and configure the AEL to activate continuous focus (spanner B, AEL/AFL, C-AF, mode 4). In other words, I press and hold the Fn (now acting as the AEL) with my thumb to activate continuous AF and keep it activated. The shutter button is just a trigger in mode 4. I can see the logic in this. Your thumb just presses hard and your index finger isn't deciding if it's taking a shot or half pressing to get focus. This is not answering your question exactly, but you might like to try it.

HughofBardfield
1st September 2008, 10:02 AM
This advice helped me:

"The thing about C-AF is that you have trained yourself on single autofocus to do this:

"Half press the shutter. Wait for the beep. Is it in focus? It is? ok, press the shutter.

"Don't do this in C-AF. Instead, get yourself in the right general area. Then, when you press the shutter, really press it all the way. Don't wait for anything. That little pause you have trained yourself to make is the difference between in focus and not in focus. If you can, hold down the button, take 5 or 6 shots, and cull later.

"For any E-camera besides the E-3, center your subject and set the camera for single focus point, center. The other two points simply don't work well enough in C-AF."
(posted here: http://www.flickr.com/groups/olympusesystem/discuss/72157604507690409/?search=C+AF )

He doesn't mention panning, of course, which is the other key thing IMHO. I had some practice with that from trying to shoot clay pigeons. Badly.

I had no success with C-AF at all before this, but now at least get some (still not reliable... lots of rejects). See http://www.flickr.com/photos/hughofbardfield/2505064229/ and http://www.flickr.com/photos/hughofbardfield/2701926108/

PeterD
1st September 2008, 04:52 PM
I have been struggling to get C-AF to work and finally, I have cracked it.

Its not too interesting a subject but at least it shows how the camera can perform. All frames have been retained.

http://e-group.uk.net/gallery/data/500/Coot_Landing-.jpg (http://e-group.uk.net/gallery/showphoto.php/photo/7932)

http://e-group.uk.net/gallery/data/500/Coot_Landing--5.jpg (http://e-group.uk.net/gallery/showphoto.php/photo/7931)

http://e-group.uk.net/gallery/data/500/Coot_Landing--4.jpg (http://e-group.uk.net/gallery/showphoto.php/photo/7930)

http://e-group.uk.net/gallery/data/500/Coot_Landing--2.jpg (http://e-group.uk.net/gallery/showphoto.php/photo/7928)

http://e-group.uk.net/gallery/data/500/Coot_Landing--3.jpg (http://e-group.uk.net/gallery/showphoto.php/photo/7929)

http://e-group.uk.net/gallery/data/500/Coot_Landing--6.jpg (http://e-group.uk.net/gallery/showphoto.php/photo/7933)

http://e-group.uk.net/gallery/data/500/Coot_Landing--7.jpg (http://e-group.uk.net/gallery/showphoto.php/photo/7934)

http://e-group.uk.net/gallery/data/500/Coot_Landing--8.jpg (http://e-group.uk.net/gallery/showphoto.php/photo/7935)

Image 1 and 2 are slightly out of focus but all others were spot on. Bearing in mind the size of the bird in the frame, not a bad performance from the camera.

Peter

PeterD
1st September 2008, 06:52 PM
I forgot to add. This sequence was shot at 5 frames per second, burst mode.

Peter

emirpprime
2nd September 2008, 11:02 AM
This big question is what got it working for you? A combination of all these or something specific? I'm sure there are many of us who would like to know! All the best,
Phil

PeterD
2nd September 2008, 11:25 AM
This big question is what got it working for you? A combination of all these or something specific? I'm sure there are many of us who would like to know! All the best,
Phil

Thanks for the above Phil. I posted the same sequence on foto fare as not everyone looks at other post areas. I thought it important to share the info.

My comments on the other thread: http://e-group.uk.net/forum/showthread.php?t=2833

'There are 3 General AF target themes to select, 16 point, 5 point and single point.

I have tried all three but found that the AF lock is very unreliable.

16 Point - the camera will lock on anything in the frame and not usually what you would want it to lock on. More failures than successes with this setting.

Single point - Great in S-AF but not C-AF. Slight movement of the camera can cause it to re-focus on something other than the target. I usually got soft focus or no focus at all. I shoot hand-held. It may well be OK on a tripod but maybe not on a monopod.

5 point - The targets are reasonably close and let you maintain lock as you pan. By far the best setting in burst mode for a relatively small target. This is the first time I have achieved this success on a 8 frame burst.

Additional findings - The camera focussed well even when other objects were in the vicinity. Today was overcast (but not as bad as it had been last week}. Some reflections from the water could have thrown the AF and under bright conditions I imagine it would.

Be interested in comments and in particular, to share other peoples experience.'

Hope this gives the background on settings used and the reason for this.

Peter

emirpprime
3rd September 2008, 08:50 AM
Thanks Peter! That is basically what I found in my very few experiences. Certainly 16 Point isn't as developed as it needs to be.
I'm glad you're having some success and thanks for the tips. I don't know if you use it already but I did find setting the "ignore big distance changes" in C-AF helps with tracking a bird that passes behind a foreground tree (for eg).
All the best,
Phil

PeterD
3rd September 2008, 09:35 AM
Thanks Peter! That is basically what I found in my very few experiences. Certainly 16 Point isn't as developed as it needs to be.
I'm glad you're having some success and thanks for the tips. I don't know if you use it already but I did find setting the "ignore big distance changes" in C-AF helps with tracking a bird that passes behind a foreground tree (for eg).
All the best,
Phil

Thanks Phil. I am very interested in that setting. Where can I find it?

What started me out on this trail was images that were produced of swallows in flight. These were taken by a Canon 5D (I think). I asked for the secret and was told C-AF multi-point target. The more targets the better!!! I believe the 5D has 48 af targets.

I am afraid the Olympus C-AF system is not developed enough as you say and that was quickly confirmed. The 5 point targets DO work and so at least we stand a chance. My thoughts on this are that Olympus would do very well to look at improving this. As I see it, it would be a firmware change and that existing hardware should be capable. OLYMPUS ARE YOU LISTENING!.

Cheers

PeterD

emirpprime
16th April 2009, 08:40 AM
Sorry to dredge this up, but I noticed I had never replied to this and had meant to.
So, in case you didn't find it:

Settings Menu 1, Spanner A, C-AF Lock - set it to on. Explanation as always on wrotniak here (http://www.wrotniak.net/photo/43/e3-sett.html)

yorky
16th April 2009, 06:01 PM
Thanks everyone, reading this has helped me to understand a wee bit more of the E3